Method for grinding grain.



WEED @TATEFs MARTIN MILLER. OF FBANKFORT-ON-THE-MAIN, GERMANY.

METHOD FOR GRINDING GRAIN.

No Drawing.

To all w/wm it may concern Be it known that I, Dr. MARTIN MILLER,

Q11 the one hand it is intended to increase the capacity of the plant by facilitating the mechanical processes during the grinding operation, and on the other hand it 1s 1n- 'tended to improve the quality of the prodnot and thereby also its baking quality. Attempts toward attaining the two just men tioned objects have already been disclosed. Thus, for instance, it is old to moisten the grain before grinding and the products during the grinding operation by means of water, whereby the baking quality of the flour or the products of the grinding operation is increased and at the same time a reduction of the friction and the heat produced thereby in grinding is obtained. In this way the capacity of the plant is in creased and troublescaused by evaporation and recondensation are reduced. It is further known to' let the aspirated air circulate and to use it over again in the same machines so that an evaporation is avoided as 1.211 as possible during the grinding operation and the content of moisture in the product is kept as constant as possible. It has been tried to reach the same object by upplying air as moist as possible to the grinding machines, and thoroughly saturating the entire atmosphere within the mill as far as posible with moisture by blowing in steam or finely difiused water. Lastly it has been tried to supply the grinding machines with dry, cooled air or dry, cooled, indifferent gases, such as carbonic acid and the like. in order to thereby facilitate the grinding operations, and. in particular the olting of the flour.

The present invention difi'ers from the known methods in that the grain is, during the grinding operation cooled down to so low a temperature that the fine powers contained in the flour or in the grain respecspecification ofLetters Patent.

Patented Jan. 5, 19715.

Application filed September 29, 1913. Serial No. 792,421.

tively, the enzyms, do not come into action and therefore the decomposition caused thereby and changes in the flour are delayed and that, furthermore, it is impossible for the precious gases from the products of the grinding toescape. By enzyms and precious gases the following is understood in flour milling: The enzyins are albuminlikecompounds which are contained in every kind of grain and fiourf Contrary to the precious gases. it is impossible for the enzyms to escape from the ground product in a gaseous form. The enzyms will, at certain conditions of temperature, produce a chemical reaction on the other components of the flour. So, for instance, the enzym -diastase will ha've'the result that at 40 to cent. and even at lower temperatures the starch of the flour is converted into sugar and dextrin. This conversion could take place, and does so to a certain extent, when the grain is heated. With the increase of the temperature this effect of the enzyms rises, and with diastase this effect reaches its highest point at 63 cent. llf the temperature is further increased the etl'ect of these enzyme again drops and if the temperature is increased beyond or 80 cent. the

power of the enzyms is weakened, and some of them may even be completely destroyed. Another such enzym which plays an important part with flour and its baking power is the so-called proteolytic enzym. This will commence to act at as low a temperature as 30 to 40 cent. being usual in every mill and will resolve the albumins of the flour, in par ticular the important gluten. Fundamentally different from the enzyms are the precious gases, which can escape from the grain during grinding. When speaking of grain, the term precious gases indicate reaction products which result from enzymatic" processes during grinding. They are the products of the decomposition of albumin and fat, and

essentially of an acid character, to the greater part-"fatty acid. It is very dificult to classify them from a chemical point of View. These precious gases will escape from the grain only simultaneously with water vapor. It is impossible for the grain to lose its previous gases if water vapor does not at the same time escape from the grain. Various substances are known in chemistry, and

undoubtedly the precious gases also belong i to these, which will not distil .over by them selves, but which are distillable by water maintain in the grain during grinding byv means of the ordinary aspiration, in-partic- Mar-during the hot season, but-neither during winter, these noxious effects of the en;

'zyfn's on thefiour will not yet appear.

As hereinbefore stated, the precious gases,

which. are'the result of enzymatic processes, are partly only produced during the grindi'ng operatiompartly they already exist in the'untouched grain as the result of biological processes in the same. As soon, now, as the temperature rises jso farthat wt ter vapor escapes from the grain, also the so-called precious gases will escape with the same. The damage thereby caused consists in the low acidity of the flour produced. By retaining the precious gases a higher degreeof acidity is insured. Besides the precious gases contain small quantities ofingredients which would improve the baking quality of the flour. The'character of the action of these ingredients has not yet .been ascertained by science, but the fact of their presence is certain."

As already stated, the escape of the precious gases depends on the simultaneous escape of water vapor. escapes, neither the precious" gases can escape from the grain or the ground product,

If no watervapor Therefore the temperatures at' which the precious gases escape are inseparably related to the temperatures at which the contents of water in the grain begins to escape. This above all depends on the condition of the grain, in particularon its content of water. The smaller the content of water in. the grain, the higher the temperature may rise withoutany loss of water and thus also any'loss of precious gases occurring. When the grain is very damp, and the pressure of the Water vapor contained in itis very high,

the temperature must be. kept very much lower than with a dry grain. Theoretica ly it may be assumed that there is no escape at zero, but practically there is no 4 3 more escaping at 15 cent. in casethe air surrounding the grain is kept at this low 1 temperature and at a hi h percentage of water, and the grain. itse f has a medium content of water of 14 to 15%. The method according' to the present invention can,

therefore, be carried out in various man It is possible to cool the grain by ing machines may be so designed, that-the rollers and the walls, with which the grain and the grinding products contact, are kept so cool, that the temperature will neither rise beyond the given limit, or, lastly, the aspiration air, which. is always employed, may be cooled down so far, that it fulfils the above mentioned conditions. Of course, it is also possible to carry out the present in vention in such a manner, that the above named means are all employed jointly or several of them combined. By the method according to the present invention it is obtained, that the enzyms do not come into action during the grinding operation, and that neither the precious gases, which may already be contained in. the .grain before grinding cannot escape so that a favorable effect toward improving the baking quality of the flour is produced in a double manner. At the same time the efiiciency of the grinding machine is increased. It is obvious,

that. the warmer the grain the larger -its.

volume. The larger, however, the volume, the greater will be the resistance which the same mass will offer to the treatment in the machine. I

I claim: p

1. A method of grinding grain, consisting in reducing the temperature of the grain before grinding to a degree sufliciently below the normal to prevent the evaporation of the water-vapor while the grinding steps are being carried out.

7 2. A method of grinding grain, consisting in reducing the temperature of the grain to a point below the normal at which maindormant and water-vapor is not generated and then grinding the grain while maintaining said" temperature belowv the the enzymatic properties of the grain re- 

